Accumulated evidence indicates that retroviruses can infect cells of the human central nervous system and may result in pathology. For example, HTLV-I infection is thought to play a role in HTLV-I-associated myelopathy/tropical spastic paraparesis, possibly through infection of neurons. It has been suggested that HTLV-II is also associated with a neurological disorder. In addition, it has been demonstrated that HIV can infect cells of the central nervous system, as well. This project will examine the molecular events following HTLV-I, HTLV-II, and HIV infection of cells derived from the human central nervous system. Particular emphasis will be placed on defining cellular genes that are activated as a result of infection and the role that the virus plays in that activation. The laboratory in which these studies will be performed is being established currently and it is anticipated that results will be available in coming years.